1. Technical Field
The present invention relates to devices for vibration stimulation of body tissue in body cavities by means of an electroactive stimulation member. The present invention further relates to methods for vibration stimulation by means of electroactive stimulation members.
2. Description of Background Art
Various medical devices are known that employ ionic electroactive polymers (EAPs) in various medical applications. Balloon catheters comprising electro active parts consisting of ionic electroactive polymers are disclosed in e.g. US 2005/0165439 and US 2010/0312322. The balloon catheters, guidewires, stents, and aneurysm coils described therein may be used for implantation or insertion in body lumens for e.g. compressing atherosclerotic plaque and for delivery of prosthetic devices. Upon application of a small voltage, typically 1 or 2 volts, the ionic EAPs undergo deformation. The ionic EAPs typically have response times of the order of a few seconds.
Dielectric elastomers constitute another class of electroactive polymers generally having faster response times compared to the abovementioned ionic EAPs. Carpi et al (Polym Int 2010; 59:407-414) presented a specific type of a hydrostatically coupled (HC) dielectric elastomer (DE) actuator referred to as a push-pull HCDE actuator having a working frequency of around100 Hz. Such hydrostatically coupled DE actuators rely on an incompressible fluid that mechanically couples a DE-based active part to a passive part interfaced to the load. Carpi et al suggest development of such actuators for use as tactile displays and cutaneous stimulators.
Stimulation in body cavities by means of mechanical vibrations is disclosed in e.g. WO 2008/138997. This PCT publication discloses a device for vibration stimulation in a body cavity, such as the nasal cavity or the intestine, of a patient. The device comprises a stimulation member and an externally arranged vibration generator for bringing the stimulation member to vibrate. Vibration stimulation in the nasal cavity may be used for treatment of e.g. rhinitis.
In order to customize vibration treatment, improved methods and devices are however called for.